And one-foubth to clatjb w



M. E. THOMAS.

.DRiLL BIT.

APPLICATION man FEB.

Patented Jan. 3, 1922.

@51% W j mmm' UNITED` STATES PATENT OFFICE.

:MARTIN n. THOMAS, or aUBnEY, Texas,"nssrenor.` or ONE-FOURTH 'ro JOHNLl. Finns, onnroonrn rowinr. n. rains, ONE-erstarrt rro Lonnie n.I-rnrivnn,

ALL OF `"EIOGrJi, TEXAS, AND ONE-FOURTH TO CLAUD W. HOPPER, OF` AUBREYTexas.

DRILL BIT.

Specification Of Letters Patent.

Patented J an. 3, 1922.

` Application led February 26, 1921. Serial No. 448,0a9.

T 0 all whom it 'may concer/a:

Be it lrnown that I, MARTIN E. THOMAS, a citizen of the United States,residing at Aubrey, in the county of Denton and State of Texas, haveinvented certain new and useful Improvements in a Drill Bit, of whichthe following is a specification.

The invention relates to improvements in drill bits, and moreparticularly to a type of the saine `adapted for use in the boringordrilling of oils wells, and the like.

The primary object of the invention is to provide for adevice of thecharacter mentioned, and one of a nature admitting of the placing anddriving of sections of the well casing downward of the drilled boresimultaneously with the boring` or drilling opera.- tion, and the readywithdrawal or replace ment of the drill bit upward or downward throughthe placed sections of the casing at any time during such boring ordrilling op eration, or at the conclusion thereof. j

A further object of the invention isto provide for a drill bit of theclass described, and one embodying features of automatic expansion andcontraction of certain of the cutting' elements thereof depending upon`the direction of the rotationof same, or of its insertion into andwithdrawal from a par tially drilled or cased bore. j

lilith the foregoing and other objects in view, the invention resides inthe` certain novel and useful construction and arrange ment of parts aswill be `hereinafter more fully described, set forth. in the appendedclaims, and illustrated in the accompanying drawings, in which j Fig. 1is a side elevation of the drill bit in operative position within thelower end of well casing section, the latter being in cross section, x

Fig. 2 is a view similar to that of Fig.` 1 with the drill bit turned aquarter revolution from its position inthe latter, i

Fig. 8 is a bottom plan view of the drill bit, and the adjacent end of awell casing section with the cutters of the former in Operative orexpanded position, the parts being relatively arranged as in Fig. 1,and,

Fig. 4 is a view similar to Fig. 3, but showing the cutters of the drillbit in inoperative or contracted position.

Referring to the drawing, wherein similar characters of referencedesignate correspending parts in the several views thereof,

the numeral 10 indicates a drillshank of a suitable weight of metal,preferably circular 1n cross section, for a major portion of its lengthand gradually increasing in diameter at its lower end to provide anenlarged head portion 11. The enlarged head portion 11 has its end faceformed to provide pairs of connected angularly disposed plane` faces12--12 and 13--13, the upper angular faces 12 and 13 ofeach pair offaces being reversely disposed one diametrically opposite the other withtheir upper edges aligning on the mean diameter of the head portion andtheir lower ends connecting theV lower angular faces 12 and 13 whichincline latorally therefrom, and are also disposed one diametricallyOpposite the other, both angular faces of each pair of such faces beingoutwardly and downwardly inclined or bev-.- eled, as shown.

Spaced above and extending parallel to the angular faces 12 and 13 ofeach pair of the angularly disposed plane faces and of slightly lessarea with respect thereto are a pair of angularly disposed integral portions or ears 14 and 15, respectively, at the inner sides of which areformed shoulder portions 16 and 17, the walls of which shoulder portionscurve outwardly from parts im* mediately adjacent the longitudinalcenter of the bit, and into the periphery of the head portion 11. Formedinthe integral portions orrears 14 and 15 are slots 18 and 19,respectively, which entend 0n lines approximating chords of the circlesformed by the peripheral wall of the head portion of the bit shank.

j Mounted on the angularly inclined faces 12 and 13 are a pair ofcircular cutters 20 and 21, respectively, the same being free forrotation on fixed journal pins 22, which are so positioned as to havetheir peripheral edges rotated within the curvature of the peripheralwall of the head portion of the bit shank. A pair of rotary cutters 23and 24 are journaled on bolts 25, one of which is slidably engaged inthe slot 18 of the car 14:, and the other similarly engaged in slot 19of the ear 15. By reason of the radial and chordal inclination of theears 14 and 15, and consequently of the slots 18 and 19, the bolts 25normally rest in the outer lower end of the latter, so that theperipheral edges of the cutters 23 and 2d are retracted to positionswithin the confines of the circle de fined by the peripheral Wall of thehead portion 11, While theybolts 25 move to the upper opposite ends ofthe `slots 1S and .19 for p'roJecting goodly portions of the peripheraledges of the cutters 23 and 24 out- Wardly of the peripheral Wall of thehead portion 11, Whenthe `bit is placed in operative position androtated in the desired clock- Wise direction. y

In the use of the drill bit thus provided, the ksame is to beoperatively connected to any suitable power mechanism, and directedend-on against the ground surface Where it is desired to drill a well.In the present construction, the drill bit is operative when rotated in.aV clock-Wise direction, when the engagement with the ground will causethe movable cutters 23 and '24 to project out- Ward of the periphery ofthe head portion ll with their journal pins or bolts at the inner upperends of the slots 18 and 19, in Whichlposition these cutters determinethe yfull diameter of the bore to be drilled, While the fixedlcutter's20'and 21 cut away the central portion of the bore, the cut or loosenedsoil being directed from both sets of cutters upward through the`inclined slot-Ways or recesses Vformed between the opposed faces of theangular faces12 and 13 of the head portion 11 and the ears 14 and 15.

Itis particularly desired in the use of this ydrill bit forl drillingoil Wells and the like,

to have a casingsection placed in the bore of the Wellafter-thesamehasbeen formed to a suitable depth, and other casingsections may be connected to the rst positioned section and driven homeinto the bore correspondingly With'its increased depth. If for anyreason it becomes necessary to Withdraw the drill vbit from the boreofthe partially drilled and encased well, the upward pull of the drill bitcauses the cutters 23 and 24 to `be'freed from contactivith the Wall vofthe bore by the bolts 25, carrying the same, tending to movelVdownwardly of the slots 18 and 19 for lthe retraction ofV these cutters,backward and inward of the peripheral wall of the head portion 1l ofthe bit shank, when the bit may be readily Withdrawn upward' of the boreof the Well and of the casing sections, the latter beingdesignated at 26of the drawings, the diamater of the head portion 11 ofV the bit shank10 being substan- 'tiallyless :than that ofthe casing sections.

shank, and means admitting of certain of the cutters movingl outwardlyof the bit shank-to cutting position outn'ardlv o'l the side Wallthereof when the bit is rested on the bottom of the bore and turned inone direction, the cutters being `Withdrawn from cutting position byturning the bit 'in the opposite direction.

2. A drill bit comprising a bit shank, rotary cutters iixedly andangularly mounted on the Working end of the bit shank. and certain otherrotary cutters angularlv mounted for movement outnf'ardly olf the bitshank-to cutting position, outwardly olfV the side Wall thereof when thebit is rested on the bottom of the bore and turned in one direction, thecutters beingl withdrawn from cutting position by turning the bit in theopposite direction.

3. A drill bit comprising a shank portion and an enlarged head portionformed to provide a plurality of angularly disposed plane faces, rotarycutters lixedly mounted on rertain of the inclined faces ol' the headportion, and certain other rotary mounted for movement outnardlxY olithe bit shank-to cutting position outwardly of the side Wall thereofwhen the bit is rested on the bottom of the bore and turned in onedirection, the cutters being witlnlrawn l'roin cutting position byturniiig the bit in the opposite direction.

4. A drill bit comprising a shank portion and an enlarged head portionformed to provide a plurality of angularly disposed plane faces, rotarycutters iixcdly mounted on certain of the inclined faces ol the headportion, and certain other rotary cutters alternately mounted formovement outwardly of the bit shank-to cutting position outwardly of theside Wall thereof when the bit is rested on the bottom of the bore andturned in one direction, the cutters being Withdrawn from cuttingposition by turning the bit in the opposite direction.

V5. A drill bit comprising a cylindrical shank portion and an enlargedcylindrical head portion formed to provide a plurality ofcorrespondingly inclined plane faces, rotary cutters fixedly mounted oucertain of the inclined faces of the head portion, and certain otherrotary cutters alternately mounted for movement outwardly of the bitshank-to cutting position outwardly o l the side Wall thereof u'hen thebit is rested on the bottom of the bore and turned in one direction, thecutters being withdrawn from cutting position by turning the bit in theopposite direction. Y'

6. A drill bit comprising a cylindrical shank portion and an enlargedcylindrical head portion formed to provide a plurality ofcorrespondingly inclined faces, alternateliY arranged inclined facesbeing under-cut to provide correspondingly inclined material cutters l l(l directing slot-Ways, rotary cutters liiiedly mounted on certain ottlie inclined tecee ot the lieed portion, and cortein other rotarycutters mounted on tlie elternetely arranged inclined trices tormovement outwerdly of the bit Slienle-to cutting position outwerdly otthe side well thereot Wlien tlie bit is rested on tlie bottoni ot thebore end turned in one direction, tlie ycutters being witlidrewn tronicutting position by turning.; tbe bit in tlie opposite direction.

7. A` drill bit conipraising,l e, drill elienlr having its working endtorined to provide e series ot engulerly inclined pleno teceecorrespondingly arranged in e cliordel direction thereof, alternatefeces et e series oit suoli feces being undercut to provide rneterieldirecting slot-Ways, lined rotary cutters mounted on certain ot tbeite/cee inwerdly ot the side well of tbe drill slienlr7 cliordnllyarranged elot-Weys torrned in the otlier ot seid trices, end rot-airycutters mounted in seid lest mentioned elot-Wnye tor tlie nievernent ottbe cutting' edges tliereot' outward ol" tlie side Woll oit the drillslienlr when operated.

8. l drill bit comprising e drill slienlr lier/ing its working endroi-ined to provide o series olf angular-ly inclined plone i'ztcescorrespondingly arranged on oliordel lines tliereot, elternete tacos ete serien ot suoli 'tacos being undercut to provide nieteriel directingslot-ways, extending in plenee parallel to the plane fecescoinplernentel thereto, lined rotary cutters mounted on certein et tlietrices inwardly et tlie eide well of the drill slienlr, slot-Waysextending` transversely ot tlie other oi" seid feces end on cliordnllinee with respect to tbe drill slienlr, and rotery cutters rnonntedinseid lest nientioned slot-Weys iter title inoveinent ot tlie cuttingedges thereof outward et tbe side Well ot tbe drill elienli nv'lienoperated.

9. A drill bit cirrnprieinp,1 e drill slienlr ot circuler cross sectionend tepered in e 'for- Werd direction to provide en enlarged Worlring;end portion, tbe 'working end portion being` torined to proride e seriesot enge lerly inclined pleno ieces correspondingly errenged on cliordellines tliereot elternete feces oit e series ot suoli teclee beingundercut to provide rneteriel directingv slot-Weys ei:- tendlng in'llenos peiellel to tbe plaine reces complement-el tlieretd lined roterycutterel mounted on certain et tbe lecce inwardly oi tliie side well oftbe drill sbonk, slot-Weye extending; transversely oit tlie other el.seid trices end on cliordel lines Witli respect to tlie drill slienlr,end rotery cutters niounted in seid lest mentioned slot-weys tor theinovernent oi tbe cutting` edges tliereot out- Werd oi" tlie side 'Welloit tlie drill elinnlr when opereted l0. drill bit barring e, plurelityot rotery cutters mounted on tlie working end tliereot, certain otcutters beingmount-ed tor :f ie bit to cuttinp` position outwor ot tbeside well tliereot when tlre bit ie rested on tbe bottoni oit the boreend turned in one directiorn tbe cutters being; 'witlidrown tronicutting1 position by turning,n tbe bit in the opposite direction. ll. ldrill. bit boring its working end torined to provide e plurelity orplaine reces eecli extending troni tie center to tlie cireurnterence enddownwardly end torwerdly inclined reletire to tlie exis tliereoi", end erotery cutter mounted on eecli of tbe Seid pleno tecee, certein ot seidcutters being` inounted lor movement outwardly oit tlie bit tocuttingposition outwardly ot the side tliereot when tlie bit is restedon the bottoni oit tlie bore end turned in one direction9 tlie cuttersbeing Witlidrewn trein cuttingv position by turning tbe bit in theopposite direction.

ln testimony Wliereot9 l etliir iny eignetnre lieretc.

lllllltllllll' ld. 'll-lllllellltl.

